Projection exposure apparatus making it possible to produce microstructures on semiconductor components are known from the prior art. These structures are conventionally produced by imaging a mask, with structures arranged on it, through a projection objective of the projection exposure apparatus onto a photosensitive layer, which is supported by a semiconductor component.
WO 2005/026843 A2 discloses an illumination system including a multiple mirror arrangement, which is sometimes also referred to as multi-mirror array (MMA). Each micromirror of this arrangement can be tilted about two orthogonal tilt axes. This makes it possible to variably illuminate a system pupil plane of the illumination system without incurring a substantial loss of light. Since the intensity distribution in the system pupil plane translated into a angular distribution in a subsequent mask plane in which the mask is to be positioned, the position of the micromirrors determine the angular distribution of light in the mask plane.
It is desirable for the micromirrors are tilted with extremely high positional precision and long-term stability. If there are inaccuracies in the alignment of the micromirrors, this causes a displacement of the light spots in the pupil plane, which can have an unfavorable effect on the imaging of the mask.